Pressure controlling means for compressors



Nov. 24, 1931. P. J. MARcHAUr PRESSURE CONTROLLING MEANS FOR COMPRESSORS Filed April 20, 1929 imA N lNvENToR Pierre J Marchal? AT TOR NEY5 Patented Nov. 24, k19,31

P'IERE 'r. MARGHAUT, onsT. DENIs'FRAnoE PATENT OFFICE rnnssURE lcNfrno'r.:r.11\sV MEAN-s ron coMrnnssoRs Application'med April 2o, 1929, serial N. 356,769, and in France May 7, 192s.

This invention. relates to a system for regulating the pressure in containers holding VfluidsV under pressure which are fed byrcompressors.

In installations which vvork by means of al fluid' under pressure and comprisei for instance acompressor for air or some other gas which is forced into areservoinwhich supplies tools or Vinstruments Working intermittently, the pressure' must needs be kept practically constant,notwithstanding the variations ofthe consumption of air due to the fact 'of putting the pneumatic tools in' or out of service.v f d f A y The system according tothe invention com.- prises va regulating distributor mounted yon the reservoir, and' comprising aservo-motor constituted for instance by a spring loadedV valve, preferably a Aball valve, in combination `With a'device for unloading-the compressor including, for example, a compressed air pis'-v ton provided With a spring acting inopp'osition l connected to the leccentric aXi'sf` of oscil- 1 lation'one or more striking levers 'controlling the suction valvev or'valves'of the compressor vfor the purpose of effecting, mcaseof an 1ncrease ofpressur'e in the reservoir, and by tion, alform of construction lof the vregulator for afcompressed -air reservoir is shown.

Figure 1 isfan axial section 'of the distributor-'regulator' Whichf is intended to bemountedf onthe compressed air reservoir.

' y'Figure'2 isalso a sectionalvievv of the diskcharging device mountedupon the cylinder of the'compressor." I l f Figure=3 shows the arrangement shown in Figure 2in a discharge position, and

assembled; f p l* ,h

yReferring to theidrawlngs, the-regulating Figure 4 is a diagram of thelapparatus as i distributor comprises la body 1A :connected to lthe compressed airfreservoir2v by means of a threaded socket 3 which is provided with a spherical closing valve 4- (Figure 1) maintained in posi-tionr in the socket 3, by means of a: tension spring 5 which can be suitably regulated andwis provided VWith a guiding 5 stem 6. The spring 'is positioned in a sleeve v7' which isvprovided with a threaded nut 8 for adjusting the spring tension.

`The chamber..9 containing the spherical valve 4 is provided With ya channel 10 communicating'through a pipe l1 (Figure 4) With one end of a chamber 12 Which is mounted 4on a pivot 13ofthe compressorV head 14. Infthey interiorkof chamber y12 is an air tight iittingrr piston v15 which is acted upon by a 65 spring 16, the vpiston being integral with the stein 17 to the extremity of which a crank 18 'isfconnected.. The crank 18 isy integral With the shaft 19, midis-.seated in a-'bracket `2() which is also secured tothe compressor head 14. The shaft19carriesthe trunnion v21vof the v.striking ,lever 22? and this trunnion is made suitably eccentric'in relation to shaft 19. :The strlking'lever 22 which controls the suction valve 23 is actuated in a manner known perse by a member such as a push yrod 24 controlledbya motor (not shown).

'The apparatus functions as follows:

1During normal Working, that is to say, as long as'the air pressure in reservoir 2 does 80 not exceeda predetermined limit, this pressure,-which acts through the socket 3 upon the loaded'valve4, is not able toovercome the resistance of the spring 6, so that the said 'valve 4 remains on its seat in the socket 3. The k.piston 15 then occupies the position indicated in Figure 2 it being pushed backby -its spring'v 16, and-*the trunnion 21 ofthe ystriking lever 22 occupies a top position, so thatthe suction valve 23 of the compressor :Works `normally and the compressor com,-V pressesthe air into the reservoir 2 for the feed of the apparatus.

If, fory instance, one or more of the apparatus fed by the reservoir 3 are stopped, the pressure in reservoir 2 vvill exceed the predetermined pressure, then the pressure acts upon the closing yvalve 4, forces that valve down by compressing the spring 5 and the valve 4 rests on its seat 25 i (Figure 2). This compressed air passes through the channel 10 and the pipe 11 to the chamber l2 and forces the piston l5 into the position indicated in Figure 8, overcoming the resiliency of the spring land compressing the same. The

' trunnion 2l of the'striking lever 22 is thereby moved downwards, so that, although the valve 23 continues to be actuated by the strik-l inglever 22, said valve 23 does not seat. The air then passes 'freely through the corresponding suction orifice during the run of the compressor, which thus stops delivering airV into the reservoir 2. v

Then the pressure again becomes normalV of the compression too frequently, theV area' of the orifice 25fis, preferably, made slightly larger: than the area ,of the orifice provided in thesocketv 3.' y Theair pressure then acts upon a larger surface When the ball Ll rests on the orifice 25, than Whenthe valve is in the position shown in Figure l, in such a manner. that the ball 4 can only bebrought. back into the ,closed positionl lshown in VFigure Y lAA when the pressure in theginterior ofthe reservoirV has/fallenftoa.value lowerthanlthat of the .normal Working pressure.

i lIt'is of lcourse possible to Areplace the ball or spherical valve e by a valve clack With doublebearing or by any otherlequivalent device; .f It is also possible to 'replace'this valve 'bya slide valve or a distributing meinf ber Vcontrolling the supply of Vcompressed air t to chamber l2, this member therefore constitutes a servo-motor Which could be combined-With any desired type of compressor 'supplydevice, acting in any suitable manner, for instance by closing the air inlet, by constant opening of the admission valve'or valve' clacks, or by'any other suitable manner. f

The invention is applicable to either portable or stationary compressed air plants, and

is in' general applicable in all casesl Where fluids under pressure, elasticor no t, are used :for'the operation of any kind of'device..

That I claim is: f

y -"i.=I-n 'a pressure controlling system for compressors, the combination, With a fluid Y compressorv andV va reservoir normally .fed

.'theieby, lof valve 'meansconnected to 'said creservoirand opened .by excess pressure thereinl above a predetermined valu'e,-actu'- ating means associated with said valve means and operable thereby upon opening of the same, a second valve associated with said compressoropened by said actuatingfmeans whereby to liberate the fluid pressure in said compressor and prevent feeding therefrom into said reservoir, auxiliary movable means operative to independently vopen said second valve, and eccentric means associated with said auxiliary movable means and moved by said actuating means upon operation of the latter and thereby controlling the opera- ,tion of said auxiliary movable means and the extent of opening of said second valve."V y

2. In a pressure controlling system for compressors, the combination, with a fluid compressor having a movable.' push rod, a suction valve and a striking lever. communieating-the movements of said push rod to said suction valve, and a reservoir normally fed by said compressor, of valve'means connected to said reservoir and openedby ex cess pressure therein above a predetermined value," actuating'means associatedvvith said valve means and operable thereby upon opening of the same, and a crankmovable by said actuating means, said'crank and said striking lever having a common mounting, While the axis of the striking lever is eccentric With respect tothe axis ofthe crank, whereby movement of said. crank by saidv actuating means is effective to alter the relative position of the axis ofisaidqstr'iking lever.

' 3. In a pressurefcontrolling system for compressors, the combination,Vv with. va. fluid compressor and a lreservoir. normally f ed thereby, Vof valve means connected, to said reservoir. and opened .by excess pressure therein above a t predetermined value, actuating means including a cylinder' connected to said valvemeans andfcontrolled thereby, a piston and a spring locatedin said'cylinder, said spring urging said piston toward one end of said cylinder and normally balancing the fluid pressure from said valve means below apredetermined value, a secondvalve associated with said compressor. opened Aby said piston upon movement thereof against said spring, whereby to liberate the fluid pressure in saidcompressor and prevent feeding therefrominto saidreservoir, auxiliary movable'means operativeto independently open said second valve, and eccentric means associated VWith said Vauxiliary movable means and also ymoved by said piston. upon movement of the latter, ,thereby .controlling fthe operation of said auxiliary movable means and the extent of opening of said second valve.

4.111 a pressure controllingrsystem `for compressors, the combination, vwith a fluid compressor having av movable push rod, a suction valve and a `striking lever communieating movements of said pushgro'd to said lsuctionlvalve Ato openpthe same, and aireservoir normally fed from said compressor, of

valve means connected to saidk reservoir and lll) opened by excess pressure therein above a predetermined value, actuatlng means including a cylinder connected to said valve means Y and controlled thereby, a piston and an associated spring located in said cylinder, said spring urging said piston toward one endof of said cylinder and normally balancing the fluid pressure from said valve means up to a predetermined value, a second valve associated With said compressor opened by said piston upon movement thereof against said spring,A whereby to lliberate the fluid pressure in said compressor and prevent feeding therefrom into said reservoir, and an eccentric partly rotatable by said piston upon movement thereof and serving as an axis for said striking lever, thereby controlling the effective operation of said striking lever and the extent of opening of said secondvvalve.

VVIn testimony whereof I have hereunto set i my hand at Paris, this eighth day of April,

PIERRE J. MARCHAUT.

fas.' 

